Information bias and lifetime mortality risks of radiation-induced cancer

Additive and multiplicative models of relative risk were used to measure the effect of cancer misclassification and DS86 random errors on lifetime risk projections in the Life Span Study (LSS) of Hiroshima and Nagasaki atomic bomb survivors. The true number of cancer deaths in each stratum of the cancer mortality cross-classification was estimated using sufficient statistics from the EM algorithm. Average survivor doses in the strata were corrected for DS86 random error ($\sigma$ = 0.45) by use of reduction factors. Poisson regression was used to model the corrected and uncorrected mortality rates with covariates for age at-time-of-bombing, age at-time-of-death and gender. Excess risks were in good agreement with risks in RERF Report 11 (Part 2) and the BEIR-V report. Bias due to DS86 random error typically ranged from $-$15% to $-$30% for both sexes, and all sites and models. The total bias, including diagnostic misclassification, of excess risk of nonleukemia for exposure to 1 Sv from age 18 to 65 under the non-constant relative projection model was $-$37.1% for males and $-$23.3% for females. Total excess risks of leukemia under the relative projection model were biased $-$27.1% for males and $-$43.4% for females. Thus, nonleukemia risks for 1 Sv from ages 18 to 85 (DRREF = 2) increased from 1.91%/Sv to 2.68%/Sv among males and from 3.23%/Sv to 4.02%/Sv among females. Leukemia excess risks increased from 0.87%/Sv to 1.10%/Sv among males and from 0.73%/Sv to 1.04%/Sv among females. Bias was dependent on the gender, site, correction method, exposure profile and projection model considered. Future studies that use LSS data for U.S. nuclear workers may be downwardly biased if lifetime risk projections are not adjusted for random and systematic errors. (Supported by U.S. NRC Grant NRC-04-091-02.) ^

MS#73 William C. Moloney, M.D., papers; 1952-1954

Dr. Moloney kept a personal journal, with photographs, for much of his two years with the Atomic Bomb Casualty Commission in Japan. Along with other scientists, he studied the biological and medical effects of ionized radiation on the survivors of the Hiroshima and Nagasaki atomic bombings. In January of 1986, Dr. Moloney donated his journal, correspondence and diary pages to the Harris County Medical Archive, whose collections were later incorporated into the Texas Medical Center Library. Dr. Moloney's journal is in relatively good shape containing a mix of handwritten notes and comments, news-clippings, photos, and ephemera. The journal is an important record of personal impressions, thoughts and details of events during a pivotal time in Japan. This 192-pagee journal gives new insights into the work of the ABCC and into the people who participated in that work. The journal covers the period from April 1952 to February 1954. In these documents, Moloney records his struggles with understanding the Japanese culture, his frustration at not being allowed to treat the survivors he studied, and his concerns, fears, hopes and revelations as he dealt with the bombing survivors and their children. The original papers are open for research at the John P. McGovern Historical Collections and Research Center in the TMC Library in Houston.